11 research outputs found
Are Deep Learning Classification Results Obtained on CT Scans Fair and Interpretable?
Following the great success of various deep learning methods in image and
object classification, the biomedical image processing society is also
overwhelmed with their applications to various automatic diagnosis cases.
Unfortunately, most of the deep learning-based classification attempts in the
literature solely focus on the aim of extreme accuracy scores, without
considering interpretability, or patient-wise separation of training and test
data. For example, most lung nodule classification papers using deep learning
randomly shuffle data and split it into training, validation, and test sets,
causing certain images from the CT scan of a person to be in the training set,
while other images of the exact same person to be in the validation or testing
image sets. This can result in reporting misleading accuracy rates and the
learning of irrelevant features, ultimately reducing the real-life usability of
these models. When the deep neural networks trained on the traditional, unfair
data shuffling method are challenged with new patient images, it is observed
that the trained models perform poorly. In contrast, deep neural networks
trained with strict patient-level separation maintain their accuracy rates even
when new patient images are tested. Heat-map visualizations of the activations
of the deep neural networks trained with strict patient-level separation
indicate a higher degree of focus on the relevant nodules. We argue that the
research question posed in the title has a positive answer only if the deep
neural networks are trained with images of patients that are strictly isolated
from the validation and testing patient sets.Comment: This version has been submitted to CAAI Transactions on Intelligence
Technology. 202
Mazabraud's Syndrome Coexisting with a Uterine Tumor Resembling an Ovarian Sex Cord Tumor (UTROSCT): a Case Report
The association of intramuscular myxoma and fibrous dysplasia is a rare disease known as Mazabraud's syndrome. We present a case of Mazabraud's syndrome coexisting with a uterine tumor and resembling an ovarian sex cord tumor (UTROSCT). This uterine tumor showed a high mitotic index and cytological atypia. To the best of our knowledge, the coexistence of the two different entities has not been reported in the literature
Value of Power Doppler and Gray-Scale US in the Diagnosis of Carpal Tunnel Syndrome: Contribution of Cross-Sectional Area just before the Tunnel Inlet as Compared with the Cross-Sectional Area at the Tunnel
Evaluation of labral pathology and hip articular cartilage in patients with femoroacetabular impingement (FAI) : comparison of multidetector CT arthrography and MR arthrography
Background: To compare the multidetector computed tomography (MDCT) arthrography (CTa) and magnetic resonance (MR) arthrography (MRa) findings with surgical findings in patients with femoroacetabular impingement (FAI) and to evaluate the diagnostic performance of these methods. Material/Methods: Labral pathology and articular cartilage were prospectively evaluated with MRa and CTa in 14 hips of 14 patients. The findings were evaluated by two musculoskeletal radiologists with 10 and 20 years of experience, respectively. Sensitivity, specificity, accuracy, and positive predictive value were determined using surgical findings as the standard of reference. Results: While the disagreement between observers was recorded in two cases of labral tearing with MRa, there was a complete consensus with CTa. Disagreement between observers was found in four cases of femoral cartilage loss with both MRa and CTa. Disagreement was also recorded in only one case of acetabular cartilage loss with both methods. The percent sensitivity, specificity, and accuracy for correctly assessing the labral tearing were as follows for MRa/CTa, respectively: 100/100, 50/100, 86/100 (p0.05) and for femoral cartilage assessment were 100/75, 90/70, 86/71 (p>0.05). Inter-observer reliability value showed excellent agreement for labral tearing with CTa (k=1.0). Inter-observer agreement was substantial to excellent with regard to acetabular cartilage assessment with MRa and CTa (k=0.76 for MRa and k=0.86 for CTa) Conclusions: Inter-observer reliability with CTa is excellent for labral tearing assessment. CTa seems to have an equal sensitivity and a higher specificity than MRa for the detection of labral pathology. MRa is better, but not statistically significantly, in demonstrating acetabular and femoral cartilage pathology
Correlation of 3-T MRI and CT findings with patient symptoms and treatment outcome in radiofrequency ablation of osteoid osteoma
Objective: The aim of this prospective study was to evaluate pre- and
post-treatment MRI and CT findings of osteoid osteoma (OO) patients
treated with radiofrequency thermo-ablation (RFTA) and to compare these
findings with visual analog scale (VAS) scores.
Methods: Sixteen patients (4 females and 12 males; mean age of 18.87 +/-
8.75 years (range: 8-37)) with OO were examined with CT and MRI, at
baseline and at an average of 3 months following the procedure. On pre-
and post-procedural CT and MRIs, OO-related findings were recorded.
Treatment success was evaluated with VAS scores.
Results: Baseline VAS scores were 8 or 9 and follow-up scores were 0 or
1, indicating no early recurrences.
Nidus diameters decreased significantly after the procedure (p = 0.027,
p = 0.002, and p = 0.002; and p = 0.001, p = 0.001, p = 0.001 for AP, ML
and CC nidus diameters for CT and MRI, respectively).
The mean nidus volume were significantly decreased after the procedure
(p = 0.001, for CT and MRI). On post-procedural images, cortical
thickening, the signal intensity and contrast enhancement of the nidus
and the extent of periostitis were significantly decreased (p = 0.019, p
= 0.001, p = 0.001 and p = 0.034, respectively). There was no
significant change in nidus calcification, perinidal cortical and
intramedullary sclerosis, periosteal reaction, bone deformity, bone
marrow and soft tissue edema, joint effusion and synovitis after the
procedure (p = 0.253, p = 0.062, p = 0.245, p = 1, p = 1, p = 0.429, p =
0.371, p = 0.625, p = 1).
Conclusion: Although the changes in imaging findings may be helpful in
early follow-up of OO patients treated with RFTA, these changes alone
cannot be used with accuracy in predicting treatment response. (C) 2019
Turkish Association of Orthopaedics and Traumatology. Publishing
services by Elsevier B.V